Simplify the following expression: $k = \dfrac{2t^2 - 5st}{6t^2 + t} - \dfrac{t^2}{6t^2 + t}$ You can assume $r,s,t \neq 0$.
Since the expressions have the same denominator we simply combine the numerators: $k = \dfrac{2t^2 - 5st - (t^2)}{6t^2 + t}$ $k = \dfrac{t^2 - 5st}{6t^2 + t}$ The numerator and denominator have a common factor of $t$, so we can simplify $k = \dfrac{t - 5s}{6t + 1}$